Consolidated Condensed Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Nov. 30, 2018	Aug. 31, 2018	Nov. 30, 2017	Aug. 31, 2017	Nov. 30, 2018	Nov. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 243,013		$ 137,109		$ 455,528	$ 354,320
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	(10,623)		(11,374)		(13,642)	23,810
Change in fair value of interest rate lock agreements	4,921		0		1,753	0
Amortization of interest rate lock agreements	(294)		(172)		(589)	(344)
Change in fair value of available-for-sale securities	0		(20)		0	0
Other comprehensive (loss) income	(5,996)	$ (6,482)	(11,566)	$ 35,032	(12,478)	23,466
Comprehensive income	$ 237,017		$ 125,543		$ 443,050	$ 377,786

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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